JP3298759B2 - Conductive resin composition - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a conductive resin composition for IC packaging, comprising a thermoplastic resin selected from at least one of polyphenylene ether resin, polystyrene resin and ABS resin, and carbon black.
By adding a hydrogenated resin to the styrene-diene block copolymer to the conductive resin composition,
The present invention relates to a conductive resin composition for IC packaging in which contamination of an IC or the like due to detachment of carbon black or the like due to abrasion at the time of contact with the IC is significantly reduced.

[0002]

2. Description of the Related Art Injection trays, vacuum forming trays, magazines, embossed carrier tapes, and the like have conventionally been used for packaging ICs and electronic components using ICs. (1) a method of applying an antistatic agent to the surface of a packaging container, (2) a method of applying a conductive paint,
(3) A method of dispersing an antistatic agent or a conductive filler or the like has been implemented.

[0003] However, the method (1) shows a sufficient antistatic effect immediately after coating, but the method (1),
The antistatic agent is likely to be detached due to outflow due to moisture and abrasion, and stable performance cannot be obtained. The surface resistivity is also 1
0 is unsuitable for ⁹ to 10 ¹² Omega about a and packaging of IC that requires strict antistatic effect. The method (2) has the drawbacks that the coating tends to be non-uniform in the manufacture, and the antistatic effect is lost due to peeling off due to abrasion, the IC is destroyed, and the lead of the IC is contaminated. In the method (3), a large amount of the antistatic agent is required, so that the physical properties of the resin are deteriorated, and the surface specific resistance value is greatly affected by humidity, so that stable performance cannot be obtained.

As the conductive filler, fine metal powder,
Examples include carbon fiber and carbon black. Of these metal powders and carbon fibers, sufficient conductivity can be obtained with a small amount of addition, but the moldability is remarkably reduced, it is difficult to disperse uniformly, and the skin layer of only the resin component is formed on the surface of the molded product. And it is difficult to obtain a stable surface specific resistance value. On the other hand, carbon black is generally used because it can be uniformly dispersed by studying kneading conditions and the like, and a stable surface specific resistance value is easily obtained, but a large amount of carbon black is added. Due to the necessity, there was a phenomenon that the fluidity and the moldability were reduced.

Conventionally, as resins for dispersing carbon black, polyvinyl chloride resins, polypropylene resins, polyethylene terephthalate resins for general use,
Polystyrene resin and ABS resin, 100 ℃
Polyphenylene ether resin for heat resistance above,
Polycarbonate resin and the like are used. Among these resins, polyphenylene ether resins are used for heat resistance, and polystyrene resins and ABS resins for general use are not significantly reduced in fluidity and moldability even when a large amount of carbon black is added. Also excellent in terms of. However, a molded article of the composition containing a large amount of carbon black has a disadvantage that carbon black is easily detached from the surface of the molded article due to abrasion.

[0006]

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned drawbacks. The present invention relates to a polyphenylene ether-based resin, a polystyrene-based resin or an ABS-based resin composition containing carbon black, and a styrene-diene block copolymer. By adding a hydrogenated resin to the polymer, in a molded article for IC packaging made of the conductive resin composition, contact and abrasion between the molded article and the IC may cause desorption of carbon black or the like. An object of the present invention is to provide a conductive resin composition in which contamination such as IC is significantly reduced.

[0007]

That is, the first aspect of the present invention is as follows.
The invention of (1) relates to hydrogenation of (A) a thermoplastic resin selected from at least one of a polyphenylene ether resin, a polystyrene resin and an ABS resin, (B) carbon black and (C) a styrene-diene block copolymer. In the conductive resin composition for IC packaging consisting of the resin obtained,
(A) 100 parts by weight of the thermoplastic resin (A), 5 to 50 parts by weight of (B) carbon black, and 100 parts by weight of the total of (A) the thermoplastic resin and (B) carbon black (C) 1 to 30 parts by weight of a resin obtained by hydrogenating a styrene-diene block copolymer, and (b) the conductive resin composition has a surface specific resistance of 10 ² to 10 ¹⁰ Ω. IC characterized in that:
It is a conductive resin composition for packaging. According to a second aspect of the present invention, there is provided the conductive material for IC packaging according to the first aspect, wherein the styrene content of the resin obtained by hydrogenating the (C) styrene-diene block copolymer is 10 to 80% by weight. Resin composition.

Hereinafter, the present invention will be described in more detail. In the present invention, (A) a polyphenylene ether-based resin,
A thermoplastic resin selected from at least one of a polystyrene resin and an ABS resin is used, and the polyphenylene ether resin refers to a resin having a polyphenylene ether resin and a polystyrene resin as main components, and a polyphenylene ether resin and a polystyrene resin. Total amount of resin 10
The content of polyphenylene ether resin in 0 parts by weight is 2
The amount is preferably from 8 to 86 parts by weight, and if it is less than 28 parts by weight, sufficient mechanical properties as a polyphenylene ether-based resin cannot be obtained, and if it exceeds 86 parts by weight, the flowability is reduced and molding processing becomes difficult. The polyphenylene ether resin is a homopolymer or a copolymer described in U.S. Pat. No. 3,383,435.

The polystyrene resin used in the present invention refers to a resin mainly composed of a general polystyrene resin or impact-resistant polystyrene resin and a mixture thereof.
The term "based resin" means a resin mainly composed of a copolymer mainly composed of three components of acrylonitrile-butadiene-styrene.

The carbon black (B) used in the present invention is furnace black, channel black, acetylene black or the like, and preferably has a large specific surface area.
High conductivity can be obtained with a small amount added to the resin. For example, C. F. (Super Condu
active Furnace); C. F. (Ele
tric Conductive Furnac
e), Ketjen Black (Lion-AKZO Corporation) and acetylene black. The amount of carbon black to be added is such that the surface specific resistance can be set to 10 ² Ω to 10 ¹⁰ Ω.
The carbon black (B) is preferably 5 to 50 parts by weight with respect to 0 parts by weight. If the amount is less than 5 parts by weight, sufficient conductivity cannot be obtained and the surface resistivity increases, and if it exceeds 50 parts by weight, the uniform dispersibility with the resin is deteriorated, and molding processing becomes difficult, and Characteristic values such as mechanical strength are reduced. If the surface resistivity exceeds 10 ¹⁰ Ω, sufficient antistatic effect cannot be obtained. If the surface resistivity is less than 10 ² Ω, electroconductivity is too high to generate electromotive force due to electromagnetic induction or electrostatic induction, and IC may be destroyed. There is.

The resin obtained by hydrogenating the styrene-diene block copolymer (C) used in the present invention is obtained by hydrogenating a styrene-diene block copolymer. (C) A resin obtained by hydrogenating a styrene-diene block copolymer has a melt flow index (JIS-K
Is less than 0.1 g / 10 min under the conditions of 200 ° C. and a load of 5 kg. If the value is less than this value, polyphenylene ether resin, polystyrene resin,
Kneading with an ABS resin becomes difficult, and a good composition cannot be obtained. As the diene of the styrene-diene block copolymer before hydrogenation, butadiene or isoprene is preferred. The styrene content in the styrene-diene block copolymer is 10 to 80% by weight, preferably 10 to 50% by weight. If the styrene content in the styrene-diene block copolymer is less than 10% by weight, the dispersibility in each of the polyphenylene ether-based resin, polystyrene-based resin and ABS-based resin is reduced, and the mechanical strength is reduced. %, The effect of improving the removal of carbon black or the like cannot be sufficiently obtained.

(C) The amount of the hydrogenated resin added to the styrene-diene block copolymer is preferably 1 to 30 parts by weight, particularly preferably 3 to 30 parts by weight, per 100 parts by weight of the total amount of the thermoplastic resin and carbon black. ２５25 parts by weight.
If the amount is less than 1 part by weight, the effect is insufficient.
If the amount exceeds 0 parts by weight, the dispersion in the polyphenylene ether-based resin, polystyrene-based resin, and ABS-based resin becomes non-uniform, resulting in a decrease in tensile modulus and a decrease in strength at break, resulting in polyphenylene ether-based resin, polystyrene-based resin, and A
The inherent properties of the BS resin are impaired.

The conductive resin composition of the present invention has a surface specific resistance of 10 ² to 1 in order to maintain sufficient moldability.
When carbon black is filled so as to be 0 ¹⁰ Ω,
The melt flow index (measured according to JIS-K-7210) is 230 ° C. and a load of 10 kg when filled in a polyphenylene ether resin, and 200 ° C. and a load of 5 kg when filled in a polystyrene resin. In the case where the ABS resin is filled under the conditions, at a temperature of 220 ° C. and a load of 10 kg, each is 0.1 g / 10 min or more.

Further, the conductive resin composition of the present invention may contain, if necessary, a lubricant, a plasticizer, a processing aid, a reinforcing agent for improving the mechanical properties of a molded article, and the like. Various additives and other resin components can be added. In the present invention, a known method such as a Banbury mixer or an extruder can be used for kneading and pelletizing various raw materials such as a resin.

[0015]

The present invention will be described in more detail with reference to the following examples. Table 1 shows the raw materials used in the present invention. Examples 1 to 7 The raw materials to be used were weighed at the composition ratios shown in Table 2, respectively.
After uniformly mixing with a high-speed mixer, the mixture was kneaded using a φ45 mm vent-type twin-screw extruder, and pelletized by a strand cut method. Next, the pelletized composition was sampled by using a φ65 mm extruder (L / D = 28) for sample M.
Sample N was formed into a sheet having a thickness of 500 μm by a T-die having a width of 0 mm.
A sample for evaluation was formed into a plate having a thickness of 1 mm × 120 mm square and a test piece for tensile measurement according to 00t). The evaluation results are shown in Tables 4 and 5. In each of the examples, no carbon black was dropped.

Comparative Examples 1 to 4 In the same manner as in Example 1, the raw materials to be used were weighed at the composition ratios shown in Table 3 and uniformly mixed by a high-speed mixer. Kneading using
Pellets were formed by a strand cut method. Next, samples M and N were prepared from the pelletized composition and evaluated. In each of the comparative examples, it was confirmed that carbon black had fallen.

[0017]

[Table 1]

[0018]

[Table 2]

[0019]

[Table 3]

[0020]

[Table 4]

[0021]

[Table 5]

Each evaluation was performed by the following method. (1) Surface specific resistance Both samples M and N were measured with a Loresta surface resistance meter (manufactured by Mitsubishi Yuka Co., Ltd.) to set the distance between the electrodes to 10 mm, and any 10 points in the sample were measured. (2) Breaking point strength and tensile modulus According to JIS-K-7113, for sample M, 2
As for the No. 1 test piece and the sample N, the No. 1 test piece was measured at a tensile speed of 10 mm / min.

(3) Presence or absence of carbon detachment QFP 14 mm on the surface of each sheet and plate sample
× 20 mm / 64 pin IC is pressed with a load of 100 g and reciprocated 100 times with a stroke of 15 mm.
Observe the lead part of C with a microscope. Evaluation was made based on the presence or absence of black deposits such as carbon black on the lead portion. (4) MFI Pellets of Examples and Comparative Examples are JIS-721.
The measurement was performed according to 0.

[0024]

As described above, in the conductive resin composition for IC packaging comprising carbon black and a thermoplastic resin selected from at least one of polyphenylene ether-based resin, polystyrene-based resin and ABS-based resin, The conductive resin composition further contains a hydrogenated resin in the styrene-diene block copolymer to significantly reduce contamination of ICs and the like caused by detachment of carbon black and the like due to abrasion at the time of contact with the ICs and the like. It is possible to obtain a reduced conductive resin composition for IC packaging.

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁷ Identification code FI // (C08L 25/04 (C08L 25/04 53:02) 53:02) (C08L 55/02 (C08L 55/02 53: 02) 53:02) (56) References JP-A-4-288363 (JP, A) JP-A-4-366165 (JP, A) JP-A-6-240131 (JP, A) JP-A-2-175754 (JP, A) JP-A-5-78568 (JP, A) JP-A-6-172633 (JP, A) JP-A-7-150000 (JP, A) JP-A 8-188710 (JP, A) ( 58) Field surveyed (Int.Cl. ⁷ , DB name) C08L 1/00-101/16 C08K 3/00-13/08 H01B 5/16 H01L 21/68

Claims (4)

(57) [Claims] (A) a thermoplastic resin selected from at least one of a polystyrene resin and an ABS resin,
In the conductive resin composition for IC packaging comprising a resin obtained by hydrogenating (B) carbon black and (C) a styrene-diene block copolymer, (A) 100 parts by weight of the thermoplastic resin (A) ) Carbon black 5-5
1 to 30 parts by weight of a resin containing (C) hydrogenated styrene-diene block copolymer based on 100 parts by weight of the total of (A) the thermoplastic resin and (B) carbon black. And (b) the conductive resin composition has a surface specific resistance of 10 ² to 10 ¹⁰ Ω. 2. The conductive resin composition for IC packaging according to claim 1, wherein the styrene content of the resin obtained by hydrogenating the styrene-diene block copolymer (C) is 10 to 80% by weight. . 3. A sheet for IC packaging comprising the conductive resin composition for IC packaging according to claim 1. 4. A molded article for IC packaging comprising the conductive resin composition for IC packaging according to claim 1.